Tourette's Disorder | Symptoms & Causes

What are the symptoms of Tourette's syndrome?

Tic behaviors seen in Tourette's syndrome change over time, and vary in frequency and complexity. The following are the most common tic behaviors associates with Tourette's syndrome. However, each child experiences symptoms differently. Symptoms may include: 

  • involuntary, purposeless, motor movements (may involve different parts of the body, such as the face, neck, shoulders, trunk, or hands)
  • head jerking
  • squinting
  • blinking
  • shrugging
  • grimacing
  • nose-twitching
  • any excessively repeated movements (i.e., foot tapping, leg jerking, scratching)

Some of the more complex tic behaviors associated with Tourette's syndrome may appear purposeful, and may include the following: 

  • kissing
  • pinching
  • sticking out the tongue or lip-smacking
  • touching behaviors
  • making obscene gestures

In addition to some, or all, of the above symptoms, Tourette's is also characterized by one or more vocal tics (meaningless sound), in order for a diagnosis to be made, including the following:   

  • grunting or moaning sounds
  • barks
  • tongue clicking
  • sniffs
  • hooting
  • obscenities
  • throat clearing, snorts, or coughs
  • squeaking noises
  • hissing
  • spitting
  • whistling
  • gurgling
  • echoing sounds or phrases repeatedly

Forty percent of children and adolescents who have Tourette's syndrome also have attention problems and 30 percent have academic difficulties. However, most have a normal intelligence and do not usually have primary learning disabilities. Twenty-five to 30 percent also experience symptoms of obsessive-compulsive disorder (OCD), which is an anxiety disorder in which a person has an unreasonable thought, fear, or activity (obsession) that he/she tries to manage through a ritualized activity (compulsion) to reduce the anxiety.

The symptoms of Tourette's syndrome may resemble other conditions or medical problems. Always consult your child's physician for a diagnosis.

What causes Tourette's syndrome? 

Tourette's syndrome is an autosomal dominant disorder. Autosomal means that both males and females are affected, and dominant means that one copy of the gene is necessary to have the condition. This means that a parent with Tourette's syndrome or a parent who has the gene for Tourette's syndrome has a 50/50 chance, with each pregnancy, to pass the gene on. Tourette's syndrome is associated with a non-genetic cause in 10 to 15 percent of children. Complications of pregnancy, low birthweight, head trauma, carbon monoxide poisoning, and encephalitis are thought to be associated with the onset of non-genetic Tourette's.

Dominant disorders exhibit something known as incomplete penetrance, which means that not everyone with the gene will have symptoms of Tourette's syndrome. In other words, if a parent passes the gene on to a child, the child may not have any symptoms of the syndrome. If a daughter inherits the gene, there is a 70 percent chance that she will have at least one of the signs of Tourette's. On the other hand, if a son inherits the gene, there is a 90 percent chance that he will have at least one of the signs of Tourette's.

Finally, dominant syndromes can also exhibit something known as variable expressivity. This means that there are differences in the expression of the Tourette's syndrome gene in different people. For example, one person with Tourette's syndrome may have obsessive-compulsive disorder, while another has a chronic tic syndrome, while another has full-blown Tourette's syndrome. In addition, there are differences in expressivity between males and females: males are more likely to have full-blown Tourette's syndrome or chronic tics, while females are more likely to have obsessive-compulsive disorder.